Proposed Canon

Casters are units that can cast MagicSpells and use scrolls. These alter the world around the Caster in some way, gather information, or otherwise provide a result that would be considered extraordinary or supernatural in the Real World. Casters are rare and therefore highly prized by the Sides they belong to. Frequently, the magical abilities provided by a specific caster form an important part of the strategy of the Side.

Every caster belongs to one magical Discipline (e.g. thinkamancy or croakamancy) and can cast spells from that discipline. Some casters can also cast spells from outside their discipline. Casters are titled by their magic class or discipline, so a caster specializing in Lookamancy is called a Lookamancer, and a caster who does general Hippiemancy would be called a Hippiemancer.

Within their discipline casters are rated according to their class, most commonly as Novice/Adept/Master. It is implied that these represent discrete steps in insight and magical abilities. However, only a few very specific examples of such abilities have been shown. This insight is gained through personal study rather than level, though increases in level do help.LIAB Text 45

Some units (e.g. Archons) can cast a limited set of spells from one or more disciplines. These are not considered casters and presumably cannot attain a higher class in a discipline or participate in caster links.

Using Magic

A caster seems to automatically know some of the spells available to him. He can also learn spells from other casters IPTSF Text 23 or work them out through experimentation. The potency of a caster's spells increases with his level IPTSF Text 20. To cast a spell a caster expends some of his juiceTBFGK 104. Since the amount of juice a caster has is limited, the amount of magic a caster can perform during one turn is also limited TBFGK 90.

All casters have extra senses. One for magic in general, and one related to their discipline. For example, all casters are able to gain an innate understanding of the magic that lies behind a scroll.LIAB Text 59 But only Thinkamancers have an innate sense for the vibrations of a G-String.LIAB Text 38

Casters can use scrolls to cast spells without expending juice. Scrolls also allow a caster access to disciplines and spells that she does not know TBFGK 126. It is unknown if there are restrictions on the disciplines or spells that can be made into scrolls.

Some casters know (and can cast) spells outside their discipline. The talent for this differs strongly between casters, from (almost) none (Sizemore Rockwell) to quite a lot (Wanda Firebaugh) TBFGK 13. The ability to cast spells outside one's discipline is dependent on levelIPTSF Text 19, current casting bonuses, and familiarity with the discipline. It is even possible for a caster to attain Adept or Master rank in a discipline that he does not belong to, though it is unknown if there are restrictions on the disciplines or spells accessible in this way.

Casters can also create magic itemsLIAB 69. No particulars about the creation process have been revealed, although Ace has been shown chanting spells over items that were previously non-magical.

Commander

Like Warlords, Casters are commanders and can lead units in combat TBFGK 84a. However, they almost never do so since they are too rare and valuable to risk. Moreover, casters do not normally have the Leadership ability and do not grant a Leadershipbonus to units under their direct command. However, some casters can grant a special bonus to particular units, presumably limited to those directly tied to their magical specialty. For example, Dirtamancers and Dollamancers provide bonuses to golems under their command, and Croakamancers provide bonuses to uncroaked units.

In some situations, casters can also grant abilities to units under their command. For example, a Croakamancer can grant the Dance-Fighting special ability to Uncroaked units under its command TBFGK 127. The Caster would likely need to possess the dance-fighting ability on their own to be able to bestow it to other units.

Caster Links

A Thinkamancer can join one or two other casters together into a caster link allowing those casters to cast powerful spells, multi-discipline spells, or create multi-discipline magical items or scrolls. The most powerful spells and items (apart from those created and used by Titans) are created by linked casters.

Caster links involving more than one Thinkamancer and two other casters are possible,Hvs.tCF 139 but this is a closely guarded secret of Thinkamancy.

Magic Kingdom

The Magic Kingdom is an island that can only be entered by casters through portals in Erfworldcities. Communities of barbarian casters live here, and the island is divided into eight sections, one for each class of magic. Casters of the various disciplines co-mingle freely, including those who are members of different sides, who may enter and leave through Portal Park to socialize or deal with other casters for their Rulers.

As barbarians, Casters from the Magic Kingdom may be hired as mercenaries, for use by the hiring Side, as Faq did with Vanna.

Casters can receive orders from Warlords and Rulers while the caster is in the Magic Kingdom.

Caster Creation

Casters are created in the same way as warlords; when a Sidepops a warlord, there is a chance it will get a caster instead. The Side also does not get to choose the type of caster it receives. Some Erf culture appears to hold that the Titans decide when a Side will pop casters, or that the need of the Ruler influences what is popped. There is no way to intentionally pop a caster.

Croaked and Decrypted Casters

Once a caster is croaked they may be uncroaked. An uncroaked caster does not retain spellcasting abilities and functions as generic uncroaked infantryErf-b1-p77a.

Speculation

Caster Creation

Casters are extremely rare, largely because they cannot be popped intentionally.

After a side pops its first caster, popping another caster becomes much more unlikely.

Many sides seem to have Thinkamancers (at least three among the combatants of the Battle for Gobwin Knob). They may be more commonly popped than members of other Disciplines. Conversely, even in the Magic Kingdom, Dirtamancers are apparently rare and in demand.

Some additional possibilities on how casters' numbers might be restricted:

As a side has existed for more turns, the chance of popping a caster decreases.

Each time a side pops a caster, the chances of popping another decreases.

Fate likely limits casters in certain ways to discourage peace. The peaceful side of Faq had a fairly decent number of casters, but was very vulnerable due to the lack of allies. The Royal Crown Coalition was a large and stable alliance, each side having a normal number of casters, but was dedicated to the purpose of enforcing Royal supremacy by crushing non-royal sides. The So-be-it Union by contrast, was a stable alliance dedicated to peace and only had 2 casters between all 4 sides on it. Alternatively, it might not be peace per se that limited the So-be-it Union's casters, but inactivity. The So-be-it Union doesn't have a lot of warfare, and it doesn't do a lot of other things either. Since units aren't being popped and croaked, leveling up, or doing any other major transactions, the So-be-it Union might not be generating enough karma to motivate Fate into creating a plan for it. And with no plan for the So-be-it Union, Fate has no reason to override their cities' production queues to produce anything other than a factory default warlord.

What casters a side gets is dependent on Signamancy. For example, a side themed around fashion designers might have a strong chance of popping a Dollamancer, a side themed around pornography might have an enhanced chance of popping a Shockmancer, and a side themed around theater might have an enhanced chance of popping Stagemancers. In this case, the number of casters may well be limited only by the strength of the side's available niches, and it might be possible for a ruler to use Signamancy to deliberately pop more casters.

There is a limit on the number of casters in the world (could be based on each type)

The odds of a caster popping decreases as the number of casters in the world increases

There is a hard limit on the number of casters in the world

It may be that sides are limited to a maximum number of casters. For example, three or fewer, with it being rare but possible to pop up to three casters. Capture, however, would be more beneficial since it allows for more than the minimum number and it means the casters may have already leveled.

Casters, Sides, and the Magic Kingdom

The Magic Kingdom is a special location that only casters can enter. Casters from active sides can enter and exit the Magic Kingdom via portals. However, many casters in the Magic Kingdom are barbarians and do not belong to sides on Erfworld, instead claiming allegiance to their discipline or to no one. The number of casters in the Magic Kingdom may, at any given time, outnumber those elsewhere on Erfworld.

Warlord Parson Gotti is able to enter the Magic Kingdom, and therefore might also be a caster. There are no other known warlord/casters in Erfworld.

Caster leveling

Leveling for casters may work differently then for other units. If casters need to kill enemy units to gain experience then leveling could be very difficult due to the fact that casters tend to be kept in capital cities. Some types, such as florists, might not even possess any magical means to croak another unit. Note that in LIAB Text 45, Sizemore says that he has gained three levels recently, two from croaking units ("from traps and combat") and one from other activities ("from all of the city rebuilding"). So it seems canon that not all caster leveling comes from croaking units.

It is possible that casters gain experience by using magic or by simply participating in a battle in any way.